Can Democrats win the Senate? Here are some pathways

Unforeseen a year ago, Democrats' now have a real chance at taking the majority in the U.S. Senate. (Gamblers in some betting markets now see it as likely, even.)

What are the potential paths for Democrats to take over the Senate — or for Republicans to block them and hold on?

The math

The current Senate has 53 Republican members. The Democratic caucus is made up of 47 Senators, or 45 Democrats and two independents (Sens. Angus King of Maine and Bernie Sanders of Vermont).

Democrats need to pick up a net of four Senate seats in order to gain a majority of 51 seats. Republican Vice President JD Vance would break a 50/50 tie, so Democrats need 51 seats minimum.

The 13 seats in play

President Donald Trump said Tuesday that the Republican Party faces an equally hard battle to retain control of the Senate and the House in November's vote. Watch the clip in the player above.

Our friends at the Cook Political Report have listed 13 Senate seats that are competitive, some more so than others. But all are on the board here.

What to know about these 13 seats:

• Republicans are on defense in nine of these seats.
• Of those Republican seats, six are considered toss-ups, aka competitive enough for either party to have a good chance of winning. That gives Democrats a range of options to get the four flips they need.
• However, Democrats are on defense in four seats themselves, including one "toss-up" in Michigan.

The nine Republican seats the Cook Political Report has in play right now:

• Six toss-ups: Alaska, Iowa, Kansas, Maine, Ohio, and Texas
• Two "likely Republican." Nebraska and South Carolina
• One "likely Democratic." North Carolina

The four competitive Democratic seats are:

• One toss-up: Michigan
• One "lean Democratic." New Hampshire
• Two "likely Democratic." Georgia and Minnesota

The three paths

A key factor when thinking about these Senate races is to assume — as both parties do — that Democrats start with one likely flip, in North Carolina.

Given that, here are three paths for the math and the map.

1. The Democrats-do-it path: Democrats get a 51-seat majority.

• Democrats win where? North Carolina, plus any four of the following six states: Alaska, Iowa, Kansas, Maine, Ohio, or Texas. That is a wide range of options at a time when Republicans in those states face tough polling. In other words, there are many possible paths here for Democrats and this is why betting markets are leaning their way.
• Democrats lose where? This scenario assumes Democrats lose in their toss-up race: Michigan. (Their candidate Abdul El-Sayed in Michigan is holding his own against Republican Mike Rogers, but this is their most vulnerable race.) Or potentially, Democrats get a surprise loss in New Hampshire.
• Result: Democrats pick up a net of at least four seats.

2. The Democrats' tsunami path: Democrats get a 54-seat majority.

• Democrats win where? North Carolina, plus all of the six toss-up states. Or perhaps, Democrats notch a surprise win in a place like South Carolina and one toss-up state, maybe Maine, stays Republican. (I'm heading to the Pine Tree State soon and will update you.) In this scenario, expect oddball deep-red places like Arkansas or Alabama to be closer than ever before as results come in.
• Democrats lose where? Nowhere. Which would be a tall order. But Democrats have done it before.
• Result: Democrats pick up seven net seats.

3. Republicans' survival path: Republicans keep a 50- or 51-seat majority or more.

• Democrats win where? In this scenario, Democrats would win North Carolina and then have just one or two toss-up wins, perhaps in Alaska and Ohio. Or perhaps Ohio and Texas. (Yes, we are in a different universe when discussing Texas this year.)
• Democrats lose where? Michigan, a toss-up seat. Thus, even if Democrats keep their seats in New Hampshire and Minnesota, and if they lose Michigan, they must win current Republican seats (as above).
• Result: Democrats pick up two or three net seats. But Republicans retain control of the Senate with a bare majority.

Watch the segment in the player above.

So, what will happen? This is a close election. But Democrats are entering voting season with some big advantages.

One is the history of a president's first midterm, in which voters generally vote with the opposing party. Another are President Donald Trump's sagging approval numbers and voter discontent with the biggest issue in any recent election: the economy.

It is a fascinating election. Get your popcorn. Or your aspirin.