With the special election just eight days away, the leader of the Tea Party Express will be on the ground in New York’s 26th district to denounce what the national organization is calling “tea party fraud.”

The well-financed national group, which played a central role in a handful of high-profile Senate elections last fall, will host two press conferences Monday with local officials and its leader, Amy Kremer.

The Tea Party Express’ involvement is not a surprise: The group has been airing radio ads to influence the May 24 special election for weeks. But the on-the-ground support signals a more significant role for the group in a contest that has surprised the political class in New York and on Capitol Hill for being far closer than it was supposed to be.

GOP nominee Jane Corwin, an independently wealthy state lawmaker, was largely expected to dominate the race, held in what may be the Empire State’s most conservative district. But the candidacy of deep-pocketed third-party candidate Jack Davis, who will appear on the ballot on the Tea Party line, has gotten in the way. Recent polling suggests that he’s draining support from Corwin, giving Democrat Kathy Hochul, the Erie County Clerk, a chance to pull off an upset.

At least one local tea party group has been attacking Davis, a Republican-turned-Democrat-turned-Republican, as a tea party fraud for several weeks. American Crossroads, which invested $650,000 on the contest so far, and other outside conservative groups have joined that refrain.

Each party’s national campaign committees have also committed at least $250,000 for television advertising.

American Action Network, another major conservative outside group, will begin airing campaign ads as well, according to Politico.

But the Tea Party Express’ involvement suggests the beginning of a ground war as well in what has suddenly become an election with national implications symbolically, if nothing else.

“The press conferences will clearly reveal Jack Davis as a big-government supporting liberal who only wishes to split the Republican vote and gain a House seat for Democrats,” reads the advisory released by the Tea Party Express.

Davis, who like Corwin has already loaned his campaign more than $2 million, has consistently slammed the involvement of outside groups as proof that his opponents are part of the “political machine” disconnected from the voters of western New York.