This is not another piece talking about the GOP challenges among women voters.  Nor is this another piece analyzing the data about the gender gap.  Those are important to do, but this does not attempt to do that.  These blog posts do a great job of that.
https://pos.org/2014/06/winning-women-what-republicans-can-do-in-2014/
https://pos.org/2014/06/winning-women-what-republicans-can-do-in-2014-2/
https://pos.org/2014/06/winning-women-what-republicans-can-do-in-2014-3/

Instead, this asks the question – what is the difference in terms of vote support among women between Republican candidates who win and Republican candidates who lose.  Aaron Blake’s interesting article on June 19th in The Fix got me thinking about what is the difference between a Republican who wins a close race and a Republican who loses.

In my analysis of the numbers, it became clear that it is not so much the size of the gender gap that matters, but the percentage that the Republican candidate gets of the women’s vote.  I had my intern, Maddy Bolger (it’s great to have one of my daughters working for me!), pull all of the Senate race results for 2010 and 2012, and pull all of the available exit polls for any race where the winner received 55{09f965da52dc6ab4c1643a77bd40d1f729d807040cd8db540234bb981a782222} of the vote or less.

And, what did I find?  In the 18 Senate races in 2010-12 where the winner received 55{09f965da52dc6ab4c1643a77bd40d1f729d807040cd8db540234bb981a782222} or less, and there were exit polls, anytime a Republican candidate got 46{09f965da52dc6ab4c1643a77bd40d1f729d807040cd8db540234bb981a782222} or more of the major party vote among women, that Republican won (seven times).  Anytime a Republican candidate received 45{09f965da52dc6ab4c1643a77bd40d1f729d807040cd8db540234bb981a782222} or less of the major party vote, the Republican lost (eleven times).

So, that makes 46{09f965da52dc6ab4c1643a77bd40d1f729d807040cd8db540234bb981a782222} the magic number.

Remember, this is the major party vote.  So, for instance, in Nevada’s 2012 U.S. Senate race, Dean Heller lost women 42{09f965da52dc6ab4c1643a77bd40d1f729d807040cd8db540234bb981a782222}-48{09f965da52dc6ab4c1643a77bd40d1f729d807040cd8db540234bb981a782222} to Shelley Berkley.  However, since only 90{09f965da52dc6ab4c1643a77bd40d1f729d807040cd8db540234bb981a782222} of women voted for either Heller OR Berkley, he actually lost the major party vote 46.6{09f965da52dc6ab4c1643a77bd40d1f729d807040cd8db540234bb981a782222} to 53.4{09f965da52dc6ab4c1643a77bd40d1f729d807040cd8db540234bb981a782222} – above the 45{09f965da52dc6ab4c1643a77bd40d1f729d807040cd8db540234bb981a782222} Mendoza line for Republican candidates.

The only two Republican winners of the last two cycles who received a majority of the vote among women in the major party vote were Roy Blunt (53{09f965da52dc6ab4c1643a77bd40d1f729d807040cd8db540234bb981a782222} of major party vote among women) and Marco Rubio (67{09f965da52dc6ab4c1643a77bd40d1f729d807040cd8db540234bb981a782222}).  The Rubio number is a little misleading – he earned 44{09f965da52dc6ab4c1643a77bd40d1f729d807040cd8db540234bb981a782222} of women, but because Charlie Crist received more votes than the Democratic nominee, Kendrick Meeks (I named him so you didn’t have to Google the 2010 Democratic Senate candidate’s name!), Meeks only polled 22{09f965da52dc6ab4c1643a77bd40d1f729d807040cd8db540234bb981a782222} of women.

The lowest any losing Republican in competitive races got of the major party vote among women was 41{09f965da52dc6ab4c1643a77bd40d1f729d807040cd8db540234bb981a782222} – that happened to three candidates.  The three races have nothing in common – Colorado 2010, Massachusetts 2012, and Pennsylvania 2012.

The data shows that Republicans do not have to win women to win close Senate races.  If that were the case, GOPers would have won five fewer seats in the Senate in the last two cycles.  But, it does show that 46{09f965da52dc6ab4c1643a77bd40d1f729d807040cd8db540234bb981a782222} is the magic number among women voters who cast their vote for either major party.

The goal for Republicans should be to get 47-48{09f965da52dc6ab4c1643a77bd40d1f729d807040cd8db540234bb981a782222} of the major party vote among women, which really underscores how important doing well among women voters is to increasing the odds of Republicans winning back the Senate.  Obviously, if women are 54{09f965da52dc6ab4c1643a77bd40d1f729d807040cd8db540234bb981a782222} of the electorate, the GOPer needs 48{09f965da52dc6ab4c1643a77bd40d1f729d807040cd8db540234bb981a782222} of women, compared to the 46{09f965da52dc6ab4c1643a77bd40d1f729d807040cd8db540234bb981a782222} they need if women are a 52{09f965da52dc6ab4c1643a77bd40d1f729d807040cd8db540234bb981a782222} share of the voters.