The Daily Digest: Walker announcement

Good morning. Here are five political stories to follow today.

1. Five things about Walker.

Wisconsin Gov. Scott Walker announced that he's running for president. As they have with all the candidates so far, NPR has a handy list of five things you may not know about the candidate. (NPR via MPR)

2. Message testing.

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Sometimes, it seems that those campaign attack ads are just thrown together at the last minute. Not true. They are tested, tested and tested again to make sure they strike just the right voters in just the right way. The New York Times has an interesting look at how one GOP super PAC is massaging their messaging against Hillary Clinton before the campaign really heats up. (The New York Times)

3. Keep it down, Don!

Republican party leaders have been asking Donald Trump to tone down his language on immigration because the GOP wants to woo immigrant voters in larger numbers this election cycle. But Trump isn't having it. (The Washington Post)

4. Nuclear deal.

Breaking news late yesterday: Diplomats are likely to announce a nuclear deal with Iran today. Details are still being worked out, but the basics involve giving Iran sanctions relief in return for Iran curbing its nuclear program. (The Associated Press)

5. Transportation deja vu.

It's like Minnesota's 2015 legislative debate over transportation funding all over again. Except this time, it's happening at the national level: Members of Congress want a bill, but they can't agree how much they should spend or how many years it should cover. The legislation affects Minnesota because the state can tap federal dollars for road projects. (National Journal)