The EU-UK Brexit Deal

320 is the magic number of votes needed to pass today’s Brexit deal in the UK parliament on Saturday

The House of Commons has 650 seats but only 639 active lawmakers. Seven MPs from the Northern Irish Sinn Fein do not take their seats and the speaker and his three deputies do not vote.

Depending on how many MPs turn out, the minimum number needed for a simple majority is sometimes lower. For instance, on the third and final vote on ex-PM Theresa May’s Brexit deal, she would have needed 316 MPs for a majority. However, she only got 286 out of 630 voting MPs to back her deal.

The parliamentary arithmetic

How many votes can Johnson expect for his deal?

• Out of the 288 Conservative MPs in the House of Commons, we estimate that about 283 will back the new Brexit deal. We expect that up to five Brexit hardliners – the most diehard of the about 20 so-called “Spartans” – will reject the deal. Johnson thus needs to find about 37 votes from outside his own ranks.

• Johnson can probably count on the 21 MPs whom he kicked out of the parliamentary party in the last two months to back the deal on the basis they are brought back into the party. Johnson has now taken his threat of a “no-deal” hard Brexit, which these MPs had rejected, off the table. If so, Johnson would still be 16 votes short, though.

• A total of nine MPs, five from Labour and four independents, backed May’s deal in the third vote. If they and the suspended Conservative MP Charlie Elphicke now back the deal, Johnson would still need to garner at least six further votes.

DUP: The king makers

How can Johnson close the gap?

If Johnson can get the Conservatives’ parliamentary partners the Northern Irish DUP on board, he has a good chance. There are 10 DUP MPs.

Otherwise, Johnson would need to persuade all of the Conservative “Spartans” to vote for the deal. If Johnson is lucky, he may get a few more MPs from the Labour Party on board, especially those who sit in pro-Brexit northern constituencies and who thus fear they could lose their seat to Brexit Party candidates if an election takes place before Brexit is sorted.

It is fair to assume that all other MPs from the other parties (SNP, Lib Dems etc.) will vote against Johnson’s deal.

Conclusion

Johnson has a chance to get the deal passed, but it is going to be tight. The House of Commons will vote on the new deal on Saturday. A lot depends on how he sells the deal to the hardliners in the coming days.