Rep. Michael McAuliffe, the only Chicago Republican serving in the Illinois House of Representatives, will head back to Springfield.

McAuliffe won one of the most closely watched legislative races in the state, taking 56 percent of the vote Tuesday to 44 percent for Democratic challenger Merry Marwig.

McAuliffe typically wins his seat by comfortable margins. His closest race came in 2002 against Robert Bugielski when McAuliffe won by eight percentage points.

But money poured in for McAuliffe this year and for Marwig in a big proxy war between Republican Gov. Bruce Rauner and powerful House Speaker Michael Madigan.

The Illinois Campaign for Political Reform said McAuliffe had $2.8 million in funds supporting him. That includes money spent by PACs to attack Marwig in advertisements.

Most of the money supporting McAuliffe came from Rauner in a bid to block House Democrats from hanging on to a veto-proof supermajority.

Marwig, who had $2.1 million spent on her behalf, got heavy financial backing from the Democratic Party and unions.

In other races:

House, 46th District: Another race between incumbent Deb Conroy, the only House Democrat from a wholly DuPage County district, and Republican challenger Heidi Holan. Two years ago, Conroy beat Holan by five percentage points. Conroy’s critics said she voted too often along party lines — with Speaker Madigan — giving her little credit for working with both parties to pass a law to incorporate civics in high school curriculum and working to consolidate 13 units of government in DuPage County to save taxpayer money. This time around, with 87 percent of precincts reporting, Conroy went up 59 percent to 41 percent to head for a third term.

“I always put my district first,” Conroy said. “My constituents know I represent their best interests — always. That’s reflected in the vote.”

House, 62nd District: A rematch between incumbent Sam Yingling, a Democrat, and Republican Rod Drobinski broke the challenger’s way early. Once all the precincts were in, Yingling won with 52 percent of the vote, a pretty significant win for Democrats. This is a Lake County race, but Republicans hit Yingling hard by buying ads in Cook County, airing commercials calling him “sleazy” and tying him to  Madigan. Total funds raised for this race reached about $4.8 million, the Illinois Campaign for Political Reform said. In 2014, Yingling won by 1,121 votes.

House, 79th District: Challenger Lindsay Parkhurst, an attorney from Kankakee, took 54 percent of the vote to claim this seat for Republicans. On the losing side: Rep. Kate Cloonen, a Democrat from Kankakee who was looking for her second term. She won the seat two years ago by 122 votes. This was another big spending race: The Illinois Campaign for Political Reform reported that the two sides combined for $5.1 million in funds. The ads got ugly. Cloonen accused Parkhurst in one  of wanting to take away seniors’ Medicare and Social Security. Both are federal programs — the state legislature doesn’t have anything to do with them. Cloonen was painted as a Madigan lackey — a common refrain by Republicans in legislative races.

House, 56th District: Two years ago Democratic Rep. Michelle Mussman of Schaumburg won this seat by 813 votes against Jim Moynihan. A new Republican challenger, Jillian Rose Bernas, was expected to make it close again. But with 89 percent of precincts reporting, Mussman led 55 percent to 45 percent.

Senate, 28th District: Laura Murphy of Des Plaines was appointed to the office in 2015 after Dan Kotowski resigned and she had a tough fight against challenger Mel Thillens, a Republican who is a familiar name on the ballot. Two years ago, Thillens, of Park Ridge, challenged Democratic Rep. Marty Moylan of Des Plaines for his house seat and lost by six percentage points. With 94 percent of precincts reporting, Murphy was headed for victory with 53 percent of the vote.

Senate, 23rd District: Republicans made a spirited push to knock off Democratic Sen. Thomas Cullerton of Villa Park. But 94 percent of the precincts in, Cullerton led challenger Seth Lewis of Bartlett with 51 percent of the vote. Political blog Capitol Fax reported Tuesday that the Republicans spent about $2.3 million. Democrats went higher at about $2.7 million.