Republicans have surged in several key Nevada races, including Sen. Dean Heller’s (R-NV) campaign, according to a poll released on Monday.

Sen. Heller leads Rep. Jacky Rosen (D-NV) by seven points—48 to 41 percent—in an Emerson College poll. Eight percent of Nevadans remain undecided, and the margin of error is 4.2 points, which puts Heller’s lead above the margin of error.

The Nevada Senate candidates both have polarizing favorability numbers. Forty-two percent of Nevadans have a favorable opinion of Sen. Heller, compared to 46 percent of Nevadans who have a negative view of the Nevada Republican. Rep. Rosen has a 45 percent unfavorable rating and a 44 percent favorable rating.

Heller’s Senate seat serves as one of the most contentious Senate seats that Republicans hope to hold in the November midterm elections. Previous polls from the New York Times and NBC News have put Heller only ahead by two points, and the Real Clear Politics polling average has put Heller’s re-election campaign ahead of Rosen by 1.7 points.

In the Nevada governor’s race, Republican Adam Laxalt leads Democrat Steve Sisolak by five points, which puts Laxalt’s lead beyond the survey’s 4.2 percent margin of error. Eleven percent of Nevadans remain undecided.

Meanwhile, in Nevada’s Third Congressional District race, Democrat Susie Lee leads Nevada businessman Danny Tarkanian by only two points. Eighteen percent of Nevadans remain undecided, and the poll has a 7.6 point margin of error, making the race a virtual dead heat.

On Breitbart News Saturday, Tarkanian said his congressional race represents the “best chance to take back a Democrat seat,” which would make it even harder for Democrats to retake the House. Democrats need to gain 24 seats in the midterm elections to achieve a one-seat majority.

“Nancy Pelosi helped recruit her to run. She’s raised her millions of dollars. She’s raised twice as much money as the incumbent race for the last election,” Tarkanian said.

Tarkanian explained that House Minority Leader Nancy Pelosi (D-CA) helped build Rep. Rosen’s campaign from the ground up.

In other Nevada congressional races, Rep. Mark Amodei leads by 23 percent, while his opponent, Clint Koble, has 16 percent support in Nevada’s Second District. In Nevada’s Fourth District, Democrat Steven Horsford has 36 percent support, while Republican Cresent Hardy has 34 percent support, and 23 percent of voters remain undecided. The margin of error is 8.1 percent.

Republicans have surged across several polls during and after the Supreme Court nomination process of Judge Brett Kavanaugh, which some pundits have called the “Kavanaugh effect.” A recent NBC News survey found that Republicans across the nation have matched Democrat interest in the midterm election.

Former White House chief of staff Reince Priebus recently contended that the Kavanaugh effect will give Republicans an extra boost in the midterm elections.

“Something incredible has happened over the last couple of weeks, and it’s called the Kavanaugh effect on Republican voters,” said Priebus.

“Before Kavanaugh, Democrats were at a ten [in enthusiasm] to defeat Trump. Republicans were at like a six. They were happy with the economy,” Priebus added. “They were happy with the wins that we had. But they weren’t at the level they needed to be. Well, now they are at a ten. So the effect is the Democrats didn’t go above ten. They are at ten. And now, the Republicans are at a ten. And so you get the juice that you need to run the machinery.”