Kentucky Secretary of State Alison Lundergan Grimes' decision to challenge Senate Minority Leader Mitch McConnell in 2014 ensures the political world one thing: This will be the nastiest race in the country.

Senate Minority Leader Mitch McConnell.

Here's why.

1. National Democrats hate McConnell.  Hate is a strong word. But it is not too strong a word for how Democrats feel about McConnell. And, the symbolic import of beating the leader of the opposition party is hard to overstate; ousting the leader of the other side -- as John Thune did when he beat Tom Daschle in 2004 -- is worth 2-3 seats in terms of how it's perceived within the party.

What that means is that a) Democratic donors from around the country will dump money into this race like they will no other in the country and ) there will be no compunction from Democrats to savage McConnell since, in so doing, they will be drumming up even more dollars. It's a virtuous cycle, politically speaking.

2. McConnell is famous/infamous for the campaigns he runs. McConnell is legendary in political circles for his willingness to unapologetically savage the person he is running against.  Witness his carpet-bombing of his 2008 Democratic opponent Bruce Lunsford in which McConnell hammered the Democrat's alleged mismanagement of health care clinics. (Here’s just one example.)

McConnell understands that his time in Washington deeply divides the Kentucky public -- and, because of that, his path to victory lies not in convincing Bluegrass State residents of his virtues but rather in making clear that his opponent is unacceptable.

(Worth noting: The other senator who has made a political living on this approach to campaigns is McConnell's Senate counterpart -- Democratic leader Harry Reid. Reid's poll numbers during his 2010 re-election race were dismal but he turned the focus of the race -- with devastating effectiveness -- onto Sharron Angle. And he won.)

3. No one (really) knows who Lundergan Grimes is. Yes, she has been elected to statewide office. And, yes, her father is the former (and longtime) chairman of the state party -- who also happens to be a friend of Bill Clinton.  But, no, no one in the state really knows who Alison Lundergan Grimes is.

Enter McConnell, the National Republican Senatorial Committee and, likely, a number of other conservative-aligned organizations. "Kentuckians have absolutely no reason to send Alison Lundergan Grimes to Washington to help pass the policies of a President whom they adamantly oppose and to elect a liberal Senate Leader who declared, 'coal makes us sick,'" said NRSC executive director Rob Collins in a statement issued today. And that's just a taste of what's to come.

Lundergan Grimes' candidacy immediately takes this race into the national spotlight. It will likely be many things over the next 18 months -- expensive, tautly contested -- but there's one thing we are certain it will be: nasty.