About 75 percent of Arizona voters cast their votes by mail instead of showing up at the polls, and this weekend marks the final push for U.S. Senate rivals Martha McSally and Kyrsten Sinema to get out the early vote before the Nov. 6 election.

Voters should mail in their ballots no later than Wednesday to guarantee they are counted.

Early-voting data shows overall voter enthusiasm at an all-time high for a midterm election, and, so far, Republicans have the clear advantage.

Pollsters say the early results are a reflection of GOP enthusiasm and the longstanding fundamentals of the red-leaning state.

For all the talk of a so-called “blue wave,” Democratic-affiliated voters are lagging behind Republicans. Democrats seemed to be holding onto their ballots longer than Republicans, although their returns surged at week's end.

“Democrats are starting to surge a bit,” said GOP pollster Paul Bentz. “The question is: Is it enough? Is it too little, too late?”

Here’s what we know, based on information from the Arizona Secretary of State's Office:

Ballot count

As of Friday, more than 854,000 ballots had been returned. This is estimated to account for an estimated 39 percent of all ballots that will be cast, including early ballots and election-day ballots.

Republican returns outpaced Democratic returns by 11 percentage points as of Friday: 44 percent of the ballots turned in so far were Republican compared with the 33 percent that were Democratic. Non-affiliated voters represented 23 percent of their share.

Almost 100,000 ballots were returned on Friday, marking the narrowest gap between the parties. That day, the ballot advantage for Republicans shrank to 8 percentage points, according to Garrett Archer, an election-data analyst for the Secretary of State's Office. Even then, Republican still held an 11 point overall advantage.

Women

Women have hit 50 percent of the overall ballots that have been returned.

Women traditionally post a high turnout during both midterm and presidential elections. On Friday, the gender returns hit parity, Archer said on Twitter.

Women have the potential to dominate early-ballot results.

"Ballots turned in by women and men are now estimated to be at parity," he wrote. "Women make up 56.2 percent of the Democratic ballots. They are now matched to their historical performance in this data point and anything higher is just icing on the cake."

All statewide candidates are pursuing moderate Republican women and independent women, seen as swing voters. Their support has traditionally been key to victory.

Republican women returns have been slower than Democratic women, Archer wrote.

Where are the Senate candidates?

Sinema will be crisscrossing the state to make her closing argument with voters and thanking volunteers in Phoenix, Tucson, Flagstaff and on the Navajo Nation.

McSally on Thursday campaigned with U.S. Sen. Joni Ernst, R-Iowa, and on Friday was at a rally in Yuma with Vice President Mike Pence. McSally's campaign did not respond to The Arizona Republic's request for her upcoming campaign schedule.

Follow the reporter on Twitter and Facebook. Reach her at yvonne.wingett@arizonarepublic.com.

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