Republicans dominate every statewide elected office in Florida but one. And it has been that way for almost a decade.

Still, Republicans worry that the U.S. Senate seat in 2016 is going to be a tough race, no matter who ends up as the party’s nominee to replace U.S. Sen. Marco Rubio, who announced last Monday that he is running for president instead.

In presidential election years, Republicans running for the Senate have struggled. The last three times Florida has had a Senate race with the presidential election on the same ballot, the Republican candidates have averaged winning just 45.9 percent of the vote, compared with the Democrats’ 51.5 percent.

So far the only Democrat to file to run in 2016 is Congressman Patrick Murphy. Fellow Rep. Alan Grayson, D-Orlando, is also weighing a campaign. The Republican field is far less certain. U.S. Rep. Vern Buchanan is among at least a half-dozen Republicans seriously considering whether to run.

But two of the expected top contenders have already dropped out. Florida Chief Financial Officer Jeff Atwater and former Florida House Speaker Will Weatherford were expected to be two of the top challengers. But within days, both announced they would skip the contest.

Sources close to Buchanan say the presidential cycle is a big reason for his hesitation to enter the race, even though he is well positioned to win a GOP primary because of his fundraising skills.

The history of U.S. Senate races in Florida in presidential election years is partly the reason why national political analysts such as the Cook Political Report and the Rothenberg & Gonzales Political Report list the race as a “pure toss-up,” even though only two Democrats have won statewide office since 1998.

Republicans have won three of the last six U.S. Senate races in Florida on the ballot during a presidential election dating back to 1980, but those victories have been mostly nailbiters, even in years when Republican presidential candidates won in near landslides.

One key players weighing a bid to replace Buchanan if he were to run for the Senate is already out of contention.

Two weeks after Sarasota County Sheriff Tom Knight said he was thinking about a congressional campaign, the two-term sheriff last week said that he would not run.

“For me it is a little too soon,” Knight said.

He said some day he might entertain running if the seat opens up again, but for now he wants to focus on being sheriff. Knight, a Republican, is up for re-election in 2016 and has already filed to run again.

“It was kind of nice thinking about it, but I’m staying where I’m at,” Knight said. “There are still things I want to accomplish as sheriff.”

Still, there would be no shortage of Republicans and Democrats interested in running for Buchanan’s 16th Congressional District seat.

State Sen. Nancy Detert, R-Venice, former state Sen. Mike Bennett, R-Sarasota, and state Rep. Greg Steube, R-Sarasota, are among the potential contenders who have confirmed they would consider running if Buchanan runs for the Senate.

About midway through Rubio’s presidential campaign speech, it hit Julio Gonzalez that he was no longer just watching a friend and ally announce he was running for president.

“I started to get overwhelmed by the bigger picture,” said Gonzalez, a state representative from Venice who is Cuban-American.

Gonzalez, who was in Miami for Rubio’s announcement last week, noted he was standing in the Freedom Tower, the place where his own parents first met as they escaped Fidel Castro’s Cuba, like so many Cuban-Americans who call Florida home.

The occasion marked a first-generation Cuban-American, like him, doing something virtuallly inconceivable for their families who had fled their homeland. Not only did Rubio rise from Miami to announce he was running for president, but he was doing so as a serious contender.

“I was overwhelmed because it was a testament to everything that is great about this nation,” Gonzalez said. “Nowhere else in the world can this happen.”

Gonzalez said that to get to Miami on Monday night, then back to Tallahassee for committee meetings the next morning was difficult, but ultimately, one of the best decisions he’s made. He said it deepened his respect and awe for his parents and what they did for their families to get to the United States, and it fanned his patriotism for this nation.

“I’m so happy I did it,” Gonzalez said.

U.S. Sen. Ted Cruz, who is also running for president, is Cuban-American as well. However, Cruz was born in Canada, where his mother is from, and was raised in Houston.

Monday: U.S. Reps. Vern Buchanan, R-Longboat Key, and Bill Shuster, R-Penn., speak to the Nokomis Area Civic Association at 5:30 p.m. at the Nokomis Community Center, 234 Nippino Trail, Nokomis. Free and open to the public.

Thursday: Former U.S. Rep. Dan Miller, R-Bradenton, speaks at the Lifelong Learning Academy’s “Lecture Series” about the partisanship in Washington. The event runs between 3 p.m. and 5 p.m., Selby Auditorium at the University of South Florida Sarasota-Manatee, 8350 N. Tamiami Trail, Sarasota. General admission is $15. To register, call 941-359-4296 or visit www.lla-sm.org.

Friday: The Lakewood Ranch Republican Club meets at noon at The Ranch Grill, 14475 State Road 70, Lakewood Ranch. Guest speaker is Xtavia Bailey, president of the Manatee County American Association of University Women. Cost is $20. For more information call 941-322-9164 or email sjc@mailmt.com.

Saturday: Political science professor Jeffrey Orenstein talks about his book “Fixing American Government-Ending Gridlock and Apathy” to the League of Women Voters of Manatee County annual luncheon at the Bradenton Country Club at noon. The meeting is at The Bradenton Country Club, 4646 Ninth Avenue West, Bradenton. Cost is $30. For reservations visit www.lwvmanatee.org by Monday. For further information call 941-729-9248 or email lwvmanatee@ yahoo.com.