Rep. Martha McSally, R-Ariz., is planning to run for Senate in 2018, Republican sources connected to her campaign confirmed Wednesday.

McSally informed House Republican lawmakers of her decision this week, Rep. Paul Gosar, R-Ariz., told the Washington Examiner. "She came and talked to us," he said. Gosar added the list of candidates could grow. "There are others still looking at it."

McSally's decision to run for Senate was likely reaffirmed by the Democratic sweep in off-year elections on Tuesday in Virginia and elsewhere. The Southeastern Arizona McSally represents is competitive: The seat has rarely been represented by Republicans and she won it by just 167 votes after a recount in 2014, a wave election for the GOP.

McSally, 51, would be one of the top Democratic targets in 2018 in an environment that shaped up as a backlash against President Trump and the Republican-led Congress, making attractive a run for the Senate seat being vacated by incumbent Republican Jeff Flake. McSally would be a strong general election candidate for the GOP in that race, if she can get through a primary.

Some conservative advocacy groups have already announced their opposition to her, and Steve Bannon, the former Trump adviser who is chairman of Breitbart News, is backing Kelli Ward in the primary. Ward also has the support of Sen. Rand Paul, R-Ky. But Republicans who have discussed the matter with McSally, a military veteran, say she is undaunted.

McSally's political team is assembling a campaign operation as she prepares to launch. Rep. Kyrsten Sinema previously announced her candidacy, and is the Democrats' preferred candidate.

Susan Ferrecchio contributed to this report.