Updated at 3:20 p.m. with additional comments from Sen. John Cornyn, R-Tex.

WASHINGTON — When Christin Davis, an acting instructor in Austin, decided to contact her senators for the first time, she was excited and nervous. She wrote out a script for her message, opposing President Donald Trump's executive order banning Syrian refugees, on a note card so she wouldn't make any mistakes.

That excitement quickly turned to exasperation.

“With Cruz, the mailbox was full,” she said. “And with Cornyn, it just hung me up right away.”

The tumultuous early weeks of Donald Trump's presidency have led to a deluge of calls to Texas congressional offices, some the result of online prompts or organized pushes from Democratic-leaning groups. It's leaving staffers struggling to keep up and some constituents frustrated at not being able to get through.

Jon Jackson, a marketing professional from Dallas, spent a full hour trying to get through to Sen. John Cornyn's office last week to ask him to vote against the confirmation of Education Secretary nominee Betsy DeVos, only to get trapped in what he described as "voicemail hell."

An automated voice would ask if he would like to speak to someone, but after a period of ringing, it would just bring him back to the main menu before ultimately disconnecting.

After his repeated efforts to get through to Cornyn’s D.C. office failed, he tried satellite offices in Austin, Dallas, San Antonio, Tyler, Lubbock and Harlingen — no luck. He could not even leave a message.

“I didn’t need specific feedback. I don’t expect to talk to the senator about this,” Jackson said. “I just wanted someone on staff to record the fact that I didn’t want Betsy DeVos confirmed.”

DeVos was confirmed by the Senate on Tuesday in a razor tight 50-50 vote with the tie broken by Vice President Mike Pence. Both Cornyn and Sen. Ted Cruz voted to confirm her.

Phil Novack, a spokesman for Cruz, attributed the holdup partly to a significant number of calls from out of the state, which he acknowledged “can unfortunately make it more difficult for Texans to reach us.” But between the senator’s Washington office and six offices in Texas, Cruz has more than two dozen staffers handling calls, he said.

“Senator Cruz looks forward to any and all opportunities to hear the concerns of Texans across the state, whether in person at the hundreds of events he has attended around the state, or via direct communication with our office,” Novack said.

Some Senate offices have recently hired additional staffers on a temporary basis to deal with what they expect to be constantly high levels of activity over the next few months. Though Cruz and Cornyn have not brought in additional help, staffers and interns who would usually be working on a variety of constituent services have had to devote more time answering the phones.

SoRelle Wyckoff, a spokeswoman for Cornyn, said the senior Texas Republican’s office can receive several thousand calls and messages per day.

“Like any phone system, when the lines are tied up, it’s harder to get through,” she said. “A member of our legislative staff reviews every opinion expressed in a phone call, voicemail, letter or email and responds to all written opinions individually as soon as they can.”

The full voicemail problems have prompted particular angst, with callers unable to leave any message during peak hours or on the weekends. Some Senate offices have upgraded their voicemail systems in recent years to a new program that has unlimited capacity.

But Cruz and Cornyn’s offices have not transitioned to that system. And the volume of calls is so high that often times as soon as they empty the voicemail, it fills right back up. They encourage constituents to reach out to them in other formats, such as email, which counts equally and will receive the same level of response as a phone call.

Cornyn argued Wednesday that the torrent of calls to his office, which he said "effectively crashed our voicemail system," were part of a "concerted campaign by the establishment to try to sink Ms. Devos’ nomination." His office received so many calls that they were unable to respond to all of them — "notwithstanding our best efforts," he said.

"But this is part of the angry response to the fact that President Trump won," Cornyn said, "and Ms. Devos seemed to be the focal point of a lot of those efforts because I think she is a game-changer when it comes to public education in the country."

'Indivisible' project

Some constituents' new enthusiasm for flooding the phone lines of their representatives stems from former congressional staffers who have highlighted the tactic as being particularly effective, especially compared with writing angry tweets or Facebook posts.

One popular call to action came from a group of former staffers out of Austin Democratic Rep. Lloyd Doggett's office, who put together a Google document called "Indivisible: A Practical Guide for Resisting the Trump Agenda" in December. After the document went viral, they created a website and a Twitter account to spread useful organizing tips.

The original nine-page document urged local activists to adopt tactics similar to the tea party, beginning with getting more involved with local members of Congress.

When Jason Sugg, an Austin psychotherapist who lives in Republican Rep. Lamar Smith's district, read the post, he was inspired to take action.

Sugg created a Facebook group for a few of his friends, to encourage them to make regular calls to Smith’s office — and within a month, the group had more than 1,500 members. Now, Sugg and others who have taken informal leadership roles within the group organize daily visits to Smith’s offices in Austin, San Antonio and Kerrville.

“They’re polite, but they aren’t very happy to see us,” Sugg said. “They listen and take some notes and tell us to contact so-and-so in D.C.”

When Sugg can’t visit the offices himself, he makes phone calls. He’s usually been able to leave a message with Smith. But like Davis, he gets “full mailbox” notices whenever he tries to call Cornyn and Cruz.

But his real goal extends beyond leaving messages for his representatives. Instead, Sugg wants to meet Smith in person, so that he can express his concerns face to face.

“If he wants a massive change in, say, our insurance system, we want him to show up in Austin and have him hear some people’s stories,” Sugg said. “And we’ve basically gotten no response.”

Senate, House offices inundated

Trump’s busy first few weeks in office have prompted constituents to weigh in on everything from Cabinet nominees to executive orders. Senate offices have been particularly inundated with calls about the Cabinet confirmation hearings.

House members are not involved with that process, but many of them report a significant uptick in calls about other issues.

Sugg wanted to express concerns about the likely repeal of the Affordable Care Act, and to talk to Smith about his position on climate change. But he was also concerned about the travel ban preventing citizens of several Muslim-majority countries from entering the country and the role of Steve Bannon, Trump’s top adviser, in the White House.

Rep. Bill Flores, R-Bryan, said he believed at least half of the calls his office has received are not from constituents but rather from "activists from other parts of the country." The onslaught of calls has not dented his confidence in the House GOP agenda.

“I know where my district is, and those calls are not representative of the district,” Flores said, noting that many calls to his office had come as a result of the Indivisible project.

Since Rep. Roger Williams, R-Austin, arrived in Congress in 2013, he said there has never been a level of calls comparable to the last few weeks. But he says the calls have not overwhelmed his office and his staff continues to respond to each one.

“There is a group on the other side, and they’re letting us know about it, but that goes with the job,” Williams said. “We don’t back off from where we stand, and we’re not going to agree on everything, but the main thing I tell my office is respond to everybody no matter what their issue is.”

Trump's foray into cost negotiations with the F-35 fighter jet program has left many residents in the Fort Worth portion of Rep. Marc Veasey's district on edge, as the planes are produced at a nearby Lockheed Martin assembly plant. That, along with Trump's federal hiring freeze, has elevated politics to the center of conversation in the Democrat's district.

“Anywhere I go in Dallas-Fort Worth when I’m back home, politics is absolutely the topic as soon as you walk into the room,” Veasey said. “You’d think the Cowboys didn’t have a 13-3 season because so many people are interested in what’s going on here.”

Rep. Randy Weber, R-Friendswood, said the rise in constituent outreach has not caught him off-guard, as he suspects congressional offices would see a similar level of activity at the outset of any new administration.

Trump "said he would go in there and shake things up and do things, and he’s doing it,” Weber said. “Is it any surprise?”