First Read is a morning briefing from Meet the Press and the NBC Political Unit on the day's most important political stories and why they matter.

Whose poll numbers are worse right now -- Clinton’s or Trump’s?

As Politico put it earlier this week, May was a rough polling month for Hillary Clinton. Her significant advantage over Donald Trump in national polls vanished, and key battleground state surveys showed dead heats, all producing plenty of Democratic handwringing and negative headlines for Clinton. So that’s certainly one way to look at the last month of poll numbers. But here’s another way: Clinton is still ahead (the national RealClear average has her lead at +1.5) -- at a time when the GOP vote has consolidated around Trump, but when the Democratic primary race is still going on. And as we’ve pointed out, Sanders voters are dragging down Clinton’s poll numbers. So given that situation, shouldn’t Trump be ahead right now? And if he’s not ahead now, when is that going to ever happen? Of course, this can all change. And it’s possible that Trump overtakes Clinton later this summer. But for that to occur, Clinton will have to get weaker than she is now, not stronger.

Clinton to slam Trump on foreign policy

NBC’s Monica Alba sets the table for Hillary Clinton’s foreign-policy address in San Diego, CA at 2:30 pm ET hitting Donald Trump. “In her first major foreign policy speech since Trump secured the Republican nomination last month, Clinton will ‘outline two competing visions of America's role in the world and two starkly different paths forward,’ according to Clinton campaign senior policy adviser Jake Sullivan. Clinton will rely heavily on her tenure as secretary of state and will ‘speak extensively’ on why she believes Trump is unqualified to be commander-in-chief, Sullivan said… Clinton will also spell out why Trump ‘is unlike any presidential nominee we've seen in modern times and he is fundamentally unfit for the job,’ Sullivan said.” But at his rally last night in Sacramento, Trump threw the first rhetorical punch. "She's one of the worst secretaries of state in the history of our country," he said, per NBC’s Ali Vitali. "Now she wants to be our president? Look, I'll be honest, she has no natural talent to be president."

Clinton should be vulnerable on foreign policy. But is Trump the candidate who can exploit that?

When it comes to foreign policy, Clinton certainly has vulnerabilities -- Libya, the Benghazi attack, the rise of ISIS. But the question is: Is Trump the Republican who can exploit them?

We have a horserace in California: Clinton 49%, Sanders 47%

The NBC/WSJ/Marist poll we released Wednesday night shows Clinton leading Bernie Sanders by just two points in California, 49%-47%, which is within the survey’s margin of error. (And California’s respected Field Poll out this morning also has Clinton ahead by just two points, 45%-43% -- down from her six-point lead back in April.) More from our NBC/WSJ/Marist poll: Clinton leads Sanders among likely voters ages 45 and older (63%-33%), self-identified Democrats (57%-40%), women (54%-41%), past Democratic primary voters (53%-42%) and whites (51%-46%). Meanwhile, Sanders leads among first-time participants (72%-28%), independents (68%-26%), those younger than 45 (66%-30%), men (54%-43%) and Latinos (49%-46%).

Let our news meet your inbox. The news and stories that matters, delivered weekday mornings. This site is protected by recaptcha

Clinton ahead by 17 points in the early vote, per our poll

The NBC/WSJ poll also finds Clinton leading among the 21% of likely Democratic primary voters in California who have already voted, 58%-41%. Among the 24% who plan to vote absentee, it’s tied at 46%-46%. And among the 55% who plan to vote on Election Day, it’s Sanders 50%, Clinton 47%. Geographically, Clinton is ahead in the Bay Area (56%-42%) and Los Angeles County (54%-40%), while Sanders has the advantage in the inland/valley areas (54%-44%) and the coastal region (58%-36%).

Don’t forget about New Jersey

But for all of the attention on California, it’s possible that Clinton could still emerge with more pledged delegates on June 7. Why? Because she’s ahead in the New Jersey polls by double digits, and the state awards 126 pledged delegates (compared with the other 93 non-CA/NJ delegates that night). As the New York Times’ Nate Cohn put it: “Does anyone else think it’s weird that there's zero interest in the New Jersey Democratic primary, the 9th largest contest in the country?”

The Democratic delegate math

Clinton is now just 67 delegates away from hitting the 2,383 magic number.

In pledged delegates, Clinton currently holds a lead of 270 delegates

Clinton 1,770 (54%)

Sanders 1,500 (46%)

Clinton must win 33% of remaining pledged delegates to get a majority in pledged delegates

Sanders must win 67% of remaining pledged delegates to get a majority in pledged delegates

In overall delegates (pledged + super), Clinton holds an overall lead of 773 delegates

Clinton must win 7% of remaining delegates to reach 2,383 magic number

Sanders must win 93% of remaining delegates to reach 2,383 magic number

Harry Reid to Sanders: “Sometimes you just have to give up”

In an interview with the AP, Senate Minority Leader Harry Reid said that Bernie Sanders shouldn’t continue his campaign through the Democratic convention in July. "I've never been too good at math but I can figure that one out. I think he better do a little mathing," Reid said. Reid added to the AP that Sanders has a right to continue his campaign through the convention, but continued: "No, I don't think he should. I don't know what that's going to prove. Sometimes you just have to give up. I've lost before. The numbers aren't there."

A reminder: Paul Ryan still hasn’t endorsed Trump

Folks, it’s been 29 days since NBC News declared Donald Trump the presumptive Republican presidential nominee. And an equal number of days have passed with the Republican House speaker, Paul Ryan, NOT endorsing Trump.

On the trail

Hillary Clinton delivers her foreign-policy speech in San Diego, CA at 2:30 pm ET before later campaigning in El Centro, CA and Perris, CA… Donald Trump holds a rally in San Jose at 10:00 pm ET… Bernie Sanders stumps in Modesto, CA and Chico, CA… And Bill Clinton hits Las Cruces, NM and Redding, CA. Don’t forget to check out the political unit’s rolling minute-to-minute coverage of all the latest 2016 developments at the On the Trail liveblog at NBCNews.com.