Nevada Democratic Rep. Jacky Rosen is “seriously considering” a run for the Senate, Democratic sources said Monday, noting that she had not made a final decision.

Politico first reported that Rosen will run against GOP Sen. Dean Heller, and could announce her campaign in the next few weeks. Two Democratic sources familiar with the matter said Rosen is seriously considering a Senate run, but she has not yet made a final decision.

“She is strongly considering it and gearing up for a campaign, but [she is] not officially a candidate,” said one Democratic source.

Former Senate Democratic Leader Harry Reid has reportedly been encouraging Rosen, a former synagogue leader, to run against Heller, according to Politico and Jon Ralston, editor of the Nevada Independent. Ralston reported that Rosen would announce her Senate campaign shortly after the second fundraising quarter ends on June 30.

Heller is arguably the most vulnerable GOP incumbent this cycle, since he is running in a state that Democratic presidential nominee Hillary Clinton won in 2016. Inside Elections with Nathan L. Gonzales rates the race Leans Republican.

Republicans wasted no time swiping at Rosen. In a statement, National Republican Senatorial Committee spokesman Michael McAdams accused Rosen of holding “radical liberal stances,” and called Reid her “puppet-master.”

Reid also recruited Rosen to run for Congress in the southern 3rd District, and she was first elected in 2016. If she were to run for the Senate, her departure would open up competitive House seat, which Inside Elections rates Tilt Democratic.