Senate Majority Leader Harry ReidHarry ReidWeek ahead: House to revive Yucca Mountain fight Warren builds her brand with 2020 down the road 'Tuesday Group' turncoats must use recess to regroup on ObamaCare MORE (D-Nev.) is hosting a fundraiser for Alison Lundergan Grimes, Senate Minority Leader Mitch McConnellMitch McConnellDisconnect: Trump, GOP not on same page GOP senator: There will never be full U.S.-Mexico border wall Overnight Tech: Dem wants to see FCC chief's net neutrality plans | New agency panel on telecom diversity | Trump calls NASA astronaut MORE's (R-Ky.) Democratic opponent.

The move marks a shift for Reid, who late last year said he wouldn't campaign against McConnell because he didn't think it was "appropriate." 

Though McConnell pledged not to campaign against Reid during his 2010 race, he also shifted course and helped Reid's GOP opponent, Sharron Angle, raise money.

In 2004, GOP Senate Leader Bill Frist (R-Tenn.) campaigned for John ThuneJohn ThuneDisconnect: Trump, GOP not on same page Seven major players in Trump's trillion infrastructure push Trump’s great tech opportunity is in spectrum sharing MORE (R-S.D.) against then-Democratic Leader Tom Daschle (D-S.D.).

The fundraiser, first reported by Kentucky news outlet Channel 2, is scheduled for Oct. 11 at a McCormick & Schmick's restaurant in Las Vegas, and is organized by the Searchlight Leadership Fund, an organization Reid founded.

Tickets range from $1,000 for an individual to $5,000 for a political action committee co-host.

The Kentucky Republican Party pounced on the fundraiser. Spokeswoman Kelsey Cooper drew ties between the candidate and Reid's positions on coal.

"It should tell Kentuckians all they need to know that the biggest supporter of Alison Lundergan Grimes' campaign is Harry Reid, the man who thinks 'coal makes us sick.' If Alison was elected to the Senate, it would ensure that liberal Harry Reid and Barack ObamaBarack Obama21 state AGs denounce DeVos for ending student loan reform Obama to net 0K for Wall Street speech: report Trump’s wall jams GOP in shutdown talks MORE continue to set national coal policy rather than a Kentucky champion for coal, Mitch McConnell," Cooper said in a statement.

Coal mining is a big industry in Kentucky, and Republicans believe Lundergan Grimes may be vulnerable because of Democratic-backed policies to curb emissions from coal-fired power plants, which opponents say will hurt the coal industry.

The Lundergan Grimes campaign and Reid's office didn't respond to requests for comment.