2018Flipped from RepublicanFinal resultsSpecial election
2018 special election for Pennsylvania's 18th District
U.S. House · Pennsylvania
Conor Lamb (D) won with 49.9% of the vote, defeating Rick Saccone (R) by 0.3 points, flipping a seat Republicans held.
Conor LambDemocrat · winner
49.9%114,102
Rick SacconeRepublican
49.5%113,347
Drew Gray MillerLibertarian
0.6%1,381
228,830 votes
Source: Federal Election CommissionUpdated Oct 3, 2026, 3:20 AM ET
The seat over time
D − R margin in this seat's races around 2018
The seat's recent races
Source: Past results: 99chambers results archive (MEDSL, Klarner, state election offices)
Polls against the result
- Poll with Lamb ahead
- Poll with Saccone ahead
- Result
| Pollster | Dates | Sample | Lamb | Saccone | Margin | Adjusted | Miss vs result | Grade | Release |
|---|---|---|---|---|---|---|---|---|---|
| Monmouth University Polling Institute | Mar 10 | 372 | 49 | 47 | D+2 | — | +1.7 | A− | Wikipedia |
| RABA Research | Mar 7 | 707 | 48 | 44 | D+4 | — | +3.7 | D | Wikipedia |
| Gravis Marketing | Mar 3 | 911 | 42 | 45 | R+3 | — | −3.3 | B− | Wikipedia |
| Emerson College | Mar 2 | 474 | 48 | 45 | D+3 | — | +2.7 | A+ | Wikipedia |
| Gravis Marketing | Feb 14 | 602 | 40 | 45 | R+5 | — | −5.3 | B− | Wikipedia |
| Monmouth University Polling Institute | Feb 14 | 320 | 45 | 49 | R+4 | — | −4.3 | A− | Wikipedia |
| DFM ResearchD-sponsored | Jan 18 | 384 | 38 | 41 | R+3 | — | −3.3 | C+ | Wikipedia |
Adjusted: after correcting for the pollster's house effect and likely-voter screens. Miss: the poll's margin minus the result; + means the poll leaned Democratic. Grade: the pollster's accuracy in past elections, A+ to D (pollster ratings).
Source: Each poll's release, via FiveThirtyEight poll listsUpdated Mar 10, 2018